| Literature DB >> 31624207 |
Michihiro Suga1,2, Fusamichi Akita3,2, Keitaro Yamashita4, Yoshiki Nakajima3, Go Ueno4, Hongjie Li3,5, Takahiro Yamane3, Kunio Hirata4, Yasufumi Umena3, Shinichiro Yonekura3, Long-Jiang Yu3, Hironori Murakami6, Takashi Nomura4,5, Tetsunari Kimura7, Minoru Kubo4,5, Seiki Baba6, Takashi Kumasaka6, Kensuke Tono4,6, Makina Yabashi4,6, Hiroshi Isobe3, Kizashi Yamaguchi8,9, Masaki Yamamoto4, Hideo Ago10, Jian-Ren Shen1.
Abstract
Photosynthetic water oxidation is catalyzed by the Mn4CaO5 cluster of photosystem II (PSII) with linear progression through five S-state intermediates (S0 to S4). To reveal the mechanism of water oxidation, we analyzed structures of PSII in the S1, S2, and S3 states by x-ray free-electron laser serial crystallography. No insertion of water was found in S2, but flipping of D1 Glu189 upon transition to S3 leads to the opening of a water channel and provides a space for incorporation of an additional oxygen ligand, resulting in an open cubane Mn4CaO6 cluster with an oxyl/oxo bridge. Structural changes of PSII between the different S states reveal cooperative action of substrate water access, proton release, and dioxygen formation in photosynthetic water oxidation.Entities:
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Year: 2019 PMID： 31624207 DOI： 10.1126/science.aax6998
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728